The ornamental design for a displayscreen or portion thereof with graphical user interface, as shown and described.
FIG. 1 is a perspective view of the first embodiment of a display screen or portion thereof with graphical user interface showing our new design; and,
FIG. 2 is a front view thereof.
The broken line showing of a display screen or portion thereof is for the purpose of illustrating environmental structure and forms no part of the claimed design. The dot-dash line(s) define the bounds of the claimed design and form no part thereof.